import requests

url = 'https://www.ems.com.cn/pc/login/index?_url=LyMv&from=emsnew'
headers = {
    'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/91.0.4472.124 Safari/537.36 Edg/91.0.864.67',
    'Accept': 'text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.9',
    'Accept-Encoding': 'gzip, deflate, br',
    'Accept-Language': 'zh-CN,zh;q=0.9',
    'Connection': 'keep-alive',
    'Host': 'www.ems.com.cn',
    'Referer': 'https://www.ems.com.cn/',
    'sec-ch-ua': '" Not;A Brand";v="99", "Microsoft Edge";v="91", "Chromium";v="91"',
    'sec-ch-ua-mobile': '?0',
    'Sec-Fetch-Dest': 'document',
    'Sec-Fetch-Mode': 'navigate',
    'Sec-Fetch-Site': 'same-origin',
    'Sec-Fetch-User': '?1',
    'Upgrade-Insecure-Requests': '1'
}
res = requests.get(url,headers=headers)
print(res.headers)